diff --git a/.github/workflows/zfs-tests-functional.yml b/.github/workflows/zfs-tests-functional.yml
index eacc95ae1617..aad3d552b236 100644
--- a/.github/workflows/zfs-tests-functional.yml
+++ b/.github/workflows/zfs-tests-functional.yml
@@ -1,71 +1,82 @@
 name: zfs-tests-functional
 
 on:
   push:
   pull_request:
 
 jobs:
   tests-functional-ubuntu:
     strategy:
       fail-fast: false
       matrix:
         os: [18.04, 20.04]
     runs-on: ubuntu-${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2
       with:
         ref: ${{ github.event.pull_request.head.sha }}
     - name: Install dependencies
       run: |
         sudo apt-get update
         sudo apt-get install --yes -qq build-essential autoconf libtool gdb lcov \
           git alien fakeroot wget curl bc fio acl \
           sysstat mdadm lsscsi parted gdebi attr dbench watchdog ksh \
           nfs-kernel-server samba rng-tools xz-utils \
           zlib1g-dev uuid-dev libblkid-dev libselinux-dev \
           xfslibs-dev libattr1-dev libacl1-dev libudev-dev libdevmapper-dev \
           libssl-dev libffi-dev libaio-dev libelf-dev libmount-dev \
           libpam0g-dev pamtester python-dev python-setuptools python-cffi \
           python-packaging python3 python3-dev python3-setuptools python3-cffi \
           libcurl4-openssl-dev python3-packaging
     - name: Autogen.sh
       run: |
         sh autogen.sh
     - name: Configure
       run: |
         ./configure --enable-debug --enable-debuginfo
     - name: Make
       run: |
         make --no-print-directory -s pkg-utils pkg-kmod
     - name: Install
       run: |
         sudo dpkg -i *.deb
         # Update order of directories to search for modules, otherwise
         #   Ubuntu will load kernel-shipped ones.
         sudo sed -i.bak 's/updates/extra updates/' /etc/depmod.d/ubuntu.conf
         sudo depmod
         sudo modprobe zfs
+        # Workaround for cloud-init bug
+        # see https://github.com/openzfs/zfs/issues/12644
+        FILE=/lib/udev/rules.d/10-cloud-init-hook-hotplug.rules
+        if [ -r "${FILE}" ]; then
+          HASH=$(md5sum "${FILE}" | awk '{ print $1 }')
+          if [ "${HASH}" = "121ff0ef1936cd2ef65aec0458a35772" ]; then
+            # Just shove a zd* exclusion right above the hotplug hook...
+            sudo sed -i -e s/'LABEL="cloudinit_hook"'/'KERNEL=="zd*", GOTO="cloudinit_end"\n&'/ "${FILE}"
+            sudo udevadm control --reload-rules
+          fi
+        fi
         # Workaround to provide additional free space for testing.
         #   https://github.com/actions/virtual-environments/issues/2840
         sudo rm -rf /usr/share/dotnet
         sudo rm -rf /opt/ghc
         sudo rm -rf "/usr/local/share/boost"
         sudo rm -rf "$AGENT_TOOLSDIRECTORY"
     - name: Tests
       run: |
         /usr/share/zfs/zfs-tests.sh -v -s 3G
     - name: Prepare artifacts
       if: failure()
       run: |
         RESULTS_PATH=$(readlink -f /var/tmp/test_results/current)
         sudo dmesg > $RESULTS_PATH/dmesg
         sudo cp /var/log/syslog $RESULTS_PATH/
         sudo chmod +r $RESULTS_PATH/*
         # Replace ':' in dir names, actions/upload-artifact doesn't support it
         for f in $(find $RESULTS_PATH -name '*:*'); do mv "$f" "${f//:/__}"; done
     - uses: actions/upload-artifact@v2
       if: failure()
       with:
         name: Test logs Ubuntu-${{ matrix.os }}
         path: /var/tmp/test_results/20*/
         if-no-files-found: ignore
diff --git a/.github/workflows/zfs-tests-sanity.yml b/.github/workflows/zfs-tests-sanity.yml
index 40a7f8ba511c..4df49461ed97 100644
--- a/.github/workflows/zfs-tests-sanity.yml
+++ b/.github/workflows/zfs-tests-sanity.yml
@@ -1,67 +1,78 @@
 name: zfs-tests-sanity
 
 on:
   push:
   pull_request:
 
 jobs:
   tests:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
       with:
         ref: ${{ github.event.pull_request.head.sha }}
     - name: Install dependencies
       run: |
         sudo apt-get update
         sudo apt-get install --yes -qq build-essential autoconf libtool gdb lcov \
           git alien fakeroot wget curl bc fio acl \
           sysstat mdadm lsscsi parted gdebi attr dbench watchdog ksh \
           nfs-kernel-server samba rng-tools xz-utils \
           zlib1g-dev uuid-dev libblkid-dev libselinux-dev \
           xfslibs-dev libattr1-dev libacl1-dev libudev-dev libdevmapper-dev \
           libssl-dev libffi-dev libaio-dev libelf-dev libmount-dev \
           libpam0g-dev pamtester python-dev python-setuptools python-cffi \
           python-packaging python3 python3-dev python3-setuptools python3-cffi \
           python3-packaging libcurl4-openssl-dev
     - name: Autogen.sh
       run: |
         sh autogen.sh
     - name: Configure
       run: |
         ./configure --enable-debug --enable-debuginfo
     - name: Make
       run: |
         make --no-print-directory -s pkg-utils pkg-kmod
     - name: Install
       run: |
         sudo dpkg -i *.deb
         # Update order of directories to search for modules, otherwise
         #   Ubuntu will load kernel-shipped ones.
         sudo sed -i.bak 's/updates/extra updates/' /etc/depmod.d/ubuntu.conf
         sudo depmod
         sudo modprobe zfs
+        # Workaround for cloud-init bug
+        # see https://github.com/openzfs/zfs/issues/12644
+        FILE=/lib/udev/rules.d/10-cloud-init-hook-hotplug.rules
+        if [ -r "${FILE}" ]; then
+          HASH=$(md5sum "${FILE}" | awk '{ print $1 }')
+          if [ "${HASH}" = "121ff0ef1936cd2ef65aec0458a35772" ]; then
+            # Just shove a zd* exclusion right above the hotplug hook...
+            sudo sed -i -e s/'LABEL="cloudinit_hook"'/'KERNEL=="zd*", GOTO="cloudinit_end"\n&'/ "${FILE}"
+            sudo udevadm control --reload-rules
+          fi
+        fi
         # Workaround to provide additional free space for testing.
         #   https://github.com/actions/virtual-environments/issues/2840
         sudo rm -rf /usr/share/dotnet
         sudo rm -rf /opt/ghc
         sudo rm -rf "/usr/local/share/boost"
         sudo rm -rf "$AGENT_TOOLSDIRECTORY"
     - name: Tests
       run: |
         /usr/share/zfs/zfs-tests.sh -v -s 3G -r sanity
     - name: Prepare artifacts
       if: failure()
       run: |
         RESULTS_PATH=$(readlink -f /var/tmp/test_results/current)
         sudo dmesg > $RESULTS_PATH/dmesg
         sudo cp /var/log/syslog $RESULTS_PATH/
         sudo chmod +r $RESULTS_PATH/*
         # Replace ':' in dir names, actions/upload-artifact doesn't support it
         for f in $(find $RESULTS_PATH -name '*:*'); do mv "$f" "${f//:/__}"; done
     - uses: actions/upload-artifact@v2
       if: failure()
       with:
         name: Test logs
         path: /var/tmp/test_results/20*/
         if-no-files-found: ignore